It appears that when God ordained Obadiah to pronounce His judgement against Edom He had endured all of Edom’s choices and His judgement against Edom would be complete with no mercy given them.

God starts the prophecy of Obadiah by telling us that a human coalition was formed to destroy Edom. From there, the rest of the prophecy is focused on God and His promises to actively destroy Edom until there is nothing left of the nation. He promises to destroy them five times, He tells them why and He finishes by promising that He will restore His people.